Shop Windows to the Universe

Learn about planets outside our solar system through Exoplanets and Alien Solar Systems by Tahir Yaqoob, Ph.D., a book in our online store book collection.
This drawing shows the water cycle.
Click on image for full size
Windows Original

Carbonates

Carbonate is a name for rocks and minerals which contain a certain form of carbon/oxygen compound known as CO32-. (CO32- is also known as the molecule carbonate).

Limestone is an example of a calcium carbonate, CaCO3, which means a combination of calcium (Ca2+) and carbonate (CO32-). Other examples of carbonates include calcite, dolomite, and marble.

Limestone is a fine-grained calcium carbonate and dissolves easily in rainwater, especially rainwater which is loaded with carbon dioxide in the form of carbonic acid. The more carbon dioxide in the rain, the more easiy limestone and marble dissolve.

As a result of human activity such as the burning of fossil fuels which inject more carbon dioxide into the air, limestone more readily dissolves. This process also helps to remove carbon dioxide from the atmosphere. Another way of looking at that same process is that a way to remove excess carbon dioxide from the atmosphere is by the dissolution of carbonates such as limestone and marble. The removal of carbon from the atmosphere and recycling in the ocean is part of the carbon cycle.

Last modified June 4, 2010 by Randy Russell.

Shop Windows to the Universe Science Store!

We have beautiful specimens of banded iron formation in our online store from Nature's Own, along with many other mineral specimens.

Windows to the Universe Community

News

Opportunities

You might also be interested in:

Cool It! Game

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

Carbon Dioxide - CO2

Carbon dioxide is a colorless and non-flammable gas at normal temperature and pressure. Although much less abundant than nitrogen and oxygen in Earth's atmosphere, carbon dioxide is an important constituent...more

Aquifer

An aquifer is the name for a layer of rock which is capable of holding a large amount of water. Some layers are better at holding water than others, for example a layer of sandstone can hold a good deal...more

Carbonates

Carbonate is a name for rocks and minerals which contain a certain form of carbon/oxygen compound known as CO32-. (CO32- is also known as the molecule carbonate). Limestone is an example of a calcium carbonate,...more

Deep Water and the CO2 cycle

The deep ocean waters are under pressure and are much colder than layers of the ocean which are closer to the surface. Dissolved carbon dioxide seems to be absent from the deep ocean water and as a result...more

Evaporation

One process which transfers water from the ground back to the atmosphere is evaporation. Evaporation is when water passes from a liquid phase to a gas phase. Rates of evaporation of water depend on factors...more

Surface Ocean Currents

The water at the ocean surface is moved primarily by winds. Large scale winds move in specific directions because they are affected by Earth’s spin and the Coriolis Effect. Because Earth spins constantly,...more

Rivers

Rivers are very important to Earth because they are major forces that shape the landscape. Also, they provide transportation and water for drinking, washing and farming. Rivers can flow on land or underground...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA